Fan Speed Control For Indoor Unit - Daikin FTXN25KEV1B Service Manual

SiBE041102_A
1.4

Fan Speed Control for Indoor Unit

Outline Phase control and fan speed control contains 9 steps: LLL, LL, SL, L, ML, M, MH, H, and HH.
The airflow rate can be automatically controlled depending on the difference between the room
thermistor temperature and the target temperature. This is done through phase control and Hall
IC control.
For more information about Hall IC, refer to the troubleshooting for fan motor on page 57.
Automatic Fan In automatic fan speed operation, the step "SL" is not available.
Speed Control
LLL
LL
L
ML
M
MH
H
HH (POWERFUL)
<Cooling>
The following drawing explains the principle of fan speed control for cooling.
*In automatic fan speed operation, upper limit is at M tap in 30 minutes from the operation start.
<Heating>
On heating mode, the fan speed is regulated according to the indoor heat exchanger
temperature and the difference between the room thermistor temperature and the target
temperature.
Note: 1. During POWERFUL operation, fan rotates at H tap + 50 rpm.
2. Fan stops during defrost operation.
COMFORT
AIRFLOW
Operation
Function and Control
Step
= The airflow rate is automatically controlled within this range when the FAN setting
button is set to automatic.
Fan speed
+2.5°C
+1.5°C
+0.5°C
The fan speed is controlled automatically.
The latest command has the priority between POWERFUL and COMFORT AIRFLOW.
Cooling Heating
(R6834)
(R6833)
Room thermistor temperature – target temperature
MH*
+3°C
M
+2°C
ML
+1°C
L
Main Functions
(R14588)
13